freebsd-skq/sys/netinet6/ipsec.h
bms 903cdeea1a Initial import of RFC 2385 (TCP-MD5) digest support.
This is the first of two commits; bringing in the kernel support first.
This can be enabled by compiling a kernel with options TCP_SIGNATURE
and FAST_IPSEC.

For the uninitiated, this is a TCP option which provides for a means of
authenticating TCP sessions which came into being before IPSEC. It is
still relevant today, however, as it is used by many commercial router
vendors, particularly with BGP, and as such has become a requirement for
interconnect at many major Internet points of presence.

Several parts of the TCP and IP headers, including the segment payload,
are digested with MD5, including a shared secret. The PF_KEY interface
is used to manage the secrets using security associations in the SADB.

There is a limitation here in that as there is no way to map a TCP flow
per-port back to an SPI without polluting tcpcb or using the SPD; the
code to do the latter is unstable at this time. Therefore this code only
supports per-host keying granularity.

Whilst FAST_IPSEC is mutually exclusive with KAME IPSEC (and thus IPv6),
TCP_SIGNATURE applies only to IPv4. For the vast majority of prospective
users of this feature, this will not pose any problem.

This implementation is output-only; that is, the option is honoured when
responding to a host initiating a TCP session, but no effort is made
[yet] to authenticate inbound traffic. This is, however, sufficient to
interwork with Cisco equipment.

Tested with a Cisco 2501 running IOS 12.0(27), and Quagga 0.96.4 with
local patches. Patches for tcpdump to validate TCP-MD5 sessions are also
available from me upon request.

Sponsored by:	sentex.net
2004-02-11 04:26:04 +00:00

393 lines
13 KiB
C

/* $FreeBSD$ */
/* $KAME: ipsec.h,v 1.69 2003/09/10 23:49:11 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* IPsec controller part.
*/
#ifndef _NETINET6_IPSEC_H_
#define _NETINET6_IPSEC_H_
#if defined(_KERNEL) && !defined(_LKM) && !defined(KLD_MODULE)
#include "opt_inet.h"
#include "opt_ipsec.h"
#endif
#include <net/pfkeyv2.h>
#include <netkey/keydb.h>
#ifdef _KERNEL
/*
* Security Policy Index
* Ensure that both address families in the "src" and "dst" are same.
* When the value of the ul_proto is ICMPv6, the port field in "src"
* specifies ICMPv6 type, and the port field in "dst" specifies ICMPv6 code.
*/
struct secpolicyindex {
struct sockaddr_storage src; /* IP src address for SP */
struct sockaddr_storage dst; /* IP dst address for SP */
u_int8_t prefs; /* prefix length in bits for src */
u_int8_t prefd; /* prefix length in bits for dst */
u_int16_t ul_proto; /* upper layer Protocol */
#ifdef notyet
uid_t uids;
uid_t uidd;
gid_t gids;
gid_t gidd;
#endif
};
/* Security Policy Data Base */
struct secpolicy {
TAILQ_ENTRY(secpolicy) tailq; /* all SPD entries, both pcb/table */
LIST_ENTRY(secpolicy) chain; /* SPD entries on table */
u_int8_t dir; /* direction of packet flow */
int readonly; /* write prohibited */
int persist; /* will never be removed */
int refcnt; /* reference count */
struct secpolicyindex *spidx; /* selector - NULL if not valid */
u_int32_t id; /* it identifies a policy in the SPD. */
#define IPSEC_MANUAL_POLICYID_MAX 0x3fff
/*
* 1 - 0x3fff are reserved for user operation.
* 0 are reserved. Others are for kernel use.
*/
struct socket *so; /* backpointer to per-socket policy */
u_int state; /* 0: dead, others: alive */
#define IPSEC_SPSTATE_DEAD 0
#define IPSEC_SPSTATE_ALIVE 1
int policy; /* DISCARD, NONE or IPSEC, see below */
struct ipsecrequest *req;
/* pointer to the ipsec request tree, */
/* if policy == IPSEC else this value == NULL.*/
/*
* lifetime handler.
* the policy can be used without limitiation if both lifetime and
* validtime are zero.
* "lifetime" is passed by sadb_lifetime.sadb_lifetime_addtime.
* "validtime" is passed by sadb_lifetime.sadb_lifetime_usetime.
*/
long created; /* time created the policy */
long lastused; /* updated every when kernel sends a packet */
long lifetime; /* duration of the lifetime of this policy */
long validtime; /* duration this policy is valid without use */
};
/* Request for IPsec */
struct ifnet;
struct ipsecrequest {
struct ipsecrequest *next;
/* pointer to next structure */
/* If NULL, it means the end of chain. */
struct secasindex saidx;/* hint for search proper SA */
/* if __ss_len == 0 then no address specified.*/
u_int level; /* IPsec level defined below. */
struct secasvar *sav; /* place holder of SA for use */
struct secpolicy *sp; /* back pointer to SP */
struct ifnet *tunifp; /* interface for tunnelling */
};
/* security policy in PCB */
struct inpcbpolicy {
struct secpolicy *sp_in;
struct secpolicy *sp_out;
int priv; /* privileged socket ? */
/* cached policy */
/* XXX 3 == IPSEC_DIR_MAX */
struct secpolicy *cache[3];
struct secpolicyindex cacheidx[3];
int cachegen[3]; /* cache generation #, the time we filled it */
int cacheflags;
#define IPSEC_PCBSP_CONNECTED 1
};
/* SP acquiring list table. */
struct secspacq {
LIST_ENTRY(secspacq) chain;
struct secpolicyindex spidx;
long created; /* for lifetime */
int count; /* for lifetime */
/* XXX: here is mbuf place holder to be sent ? */
};
struct ipsecaux {
int hdrs; /* # of ipsec headers */
};
#endif /* _KERNEL */
/* according to IANA assignment, port 0x0000 and proto 0xff are reserved. */
#define IPSEC_PORT_ANY 0
#define IPSEC_ULPROTO_ANY 255
#define IPSEC_PROTO_ANY 255
/* mode of security protocol */
/* NOTE: DON'T use IPSEC_MODE_ANY at SPD. It's only use in SAD */
#define IPSEC_MODE_ANY 0 /* i.e. wildcard. */
#define IPSEC_MODE_TRANSPORT 1
#define IPSEC_MODE_TUNNEL 2
#define IPSEC_MODE_TCPMD5 3 /* TCP MD5 mode */
/*
* Direction of security policy.
* NOTE: Since INVALID is used just as flag.
* The other are used for loop counter too.
*/
#define IPSEC_DIR_ANY 0
#define IPSEC_DIR_INBOUND 1
#define IPSEC_DIR_OUTBOUND 2
#define IPSEC_DIR_MAX 3
#define IPSEC_DIR_INVALID 4
/* Policy level */
/*
* IPSEC, ENTRUST and BYPASS are allowed for setsockopt() in PCB,
* DISCARD, IPSEC and NONE are allowed for setkey() in SPD.
* DISCARD and NONE are allowed for system default.
*/
#define IPSEC_POLICY_DISCARD 0 /* discard the packet */
#define IPSEC_POLICY_NONE 1 /* bypass IPsec engine */
#define IPSEC_POLICY_IPSEC 2 /* pass to IPsec */
#define IPSEC_POLICY_ENTRUST 3 /* consulting SPD if present. */
#define IPSEC_POLICY_BYPASS 4 /* only for privileged socket. */
#define IPSEC_POLICY_TCP 5 /* TCP MD5 policy */
/* Security protocol level */
#define IPSEC_LEVEL_DEFAULT 0 /* reference to system default */
#define IPSEC_LEVEL_USE 1 /* use SA if present. */
#define IPSEC_LEVEL_REQUIRE 2 /* require SA. */
#define IPSEC_LEVEL_UNIQUE 3 /* unique SA. */
#define IPSEC_MANUAL_REQID_MAX 0x3fff
/*
* if security policy level == unique, this id
* indicate to a relative SA for use, else is
* zero.
* 1 - 0x3fff are reserved for manual keying.
* 0 are reserved for above reason. Others is
* for kernel use.
* Note that this id doesn't identify SA
* by only itself.
*/
#define IPSEC_REPLAYWSIZE 32
/* statistics for ipsec processing */
struct ipsecstat {
u_quad_t in_success; /* succeeded inbound process */
u_quad_t in_polvio;
/* security policy violation for inbound process */
u_quad_t in_nosa; /* inbound SA is unavailable */
u_quad_t in_inval; /* inbound processing failed due to EINVAL */
u_quad_t in_nomem; /* inbound processing failed due to ENOBUFS */
u_quad_t in_badspi; /* failed getting a SPI */
u_quad_t in_ahreplay; /* AH replay check failed */
u_quad_t in_espreplay; /* ESP replay check failed */
u_quad_t in_ahauthsucc; /* AH authentication success */
u_quad_t in_ahauthfail; /* AH authentication failure */
u_quad_t in_espauthsucc; /* ESP authentication success */
u_quad_t in_espauthfail; /* ESP authentication failure */
u_quad_t in_esphist[256];
u_quad_t in_ahhist[256];
u_quad_t in_comphist[256];
u_quad_t out_success; /* succeeded outbound process */
u_quad_t out_polvio;
/* security policy violation for outbound process */
u_quad_t out_nosa; /* outbound SA is unavailable */
u_quad_t out_inval; /* outbound process failed due to EINVAL */
u_quad_t out_nomem; /* inbound processing failed due to ENOBUFS */
u_quad_t out_noroute; /* there is no route */
u_quad_t out_esphist[256];
u_quad_t out_ahhist[256];
u_quad_t out_comphist[256];
u_quad_t spdcachelookup;
u_quad_t spdcachemiss;
};
/*
* Definitions for IPsec & Key sysctl operations.
*/
/*
* Names for IPsec & Key sysctl objects
*/
#define IPSECCTL_STATS 1 /* stats */
#define IPSECCTL_DEF_POLICY 2
#define IPSECCTL_DEF_ESP_TRANSLEV 3 /* int; ESP transport mode */
#define IPSECCTL_DEF_ESP_NETLEV 4 /* int; ESP tunnel mode */
#define IPSECCTL_DEF_AH_TRANSLEV 5 /* int; AH transport mode */
#define IPSECCTL_DEF_AH_NETLEV 6 /* int; AH tunnel mode */
#if 0 /* obsolete, do not reuse */
#define IPSECCTL_INBOUND_CALL_IKE 7
#endif
#define IPSECCTL_AH_CLEARTOS 8
#define IPSECCTL_AH_OFFSETMASK 9
#define IPSECCTL_DFBIT 10
#define IPSECCTL_ECN 11
#define IPSECCTL_DEBUG 12
#define IPSECCTL_ESP_RANDPAD 13
#define IPSECCTL_MAXID 14
#define IPSECCTL_NAMES { \
{ 0, 0 }, \
{ 0, 0 }, \
{ "def_policy", CTLTYPE_INT }, \
{ "esp_trans_deflev", CTLTYPE_INT }, \
{ "esp_net_deflev", CTLTYPE_INT }, \
{ "ah_trans_deflev", CTLTYPE_INT }, \
{ "ah_net_deflev", CTLTYPE_INT }, \
{ 0, 0 }, \
{ "ah_cleartos", CTLTYPE_INT }, \
{ "ah_offsetmask", CTLTYPE_INT }, \
{ "dfbit", CTLTYPE_INT }, \
{ "ecn", CTLTYPE_INT }, \
{ "debug", CTLTYPE_INT }, \
{ "esp_randpad", CTLTYPE_INT }, \
}
#define IPSEC6CTL_NAMES { \
{ 0, 0 }, \
{ 0, 0 }, \
{ "def_policy", CTLTYPE_INT }, \
{ "esp_trans_deflev", CTLTYPE_INT }, \
{ "esp_net_deflev", CTLTYPE_INT }, \
{ "ah_trans_deflev", CTLTYPE_INT }, \
{ "ah_net_deflev", CTLTYPE_INT }, \
{ 0, 0 }, \
{ 0, 0 }, \
{ 0, 0 }, \
{ 0, 0 }, \
{ "ecn", CTLTYPE_INT }, \
{ "debug", CTLTYPE_INT }, \
{ "esp_randpad", CTLTYPE_INT }, \
}
#ifdef _KERNEL
struct ipsec_output_state {
struct mbuf *m;
struct route *ro;
struct sockaddr *dst;
int encap;
};
struct ipsec_history {
int ih_proto;
u_int32_t ih_spi;
};
extern int ipsec_debug;
#ifdef INET
extern struct ipsecstat ipsecstat;
extern struct secpolicy *ip4_def_policy;
extern int ip4_esp_trans_deflev;
extern int ip4_esp_net_deflev;
extern int ip4_ah_trans_deflev;
extern int ip4_ah_net_deflev;
extern int ip4_ah_cleartos;
extern int ip4_ah_offsetmask;
extern int ip4_ipsec_dfbit;
extern int ip4_ipsec_ecn;
extern int ip4_esp_randpad;
#endif
#define ipseclog(x) do { if (ipsec_debug) log x; } while (/*CONSTCOND*/ 0)
extern int ipsec_pcbconn __P((struct inpcbpolicy *));
extern int ipsec_pcbdisconn __P((struct inpcbpolicy *));
extern int ipsec_invalpcbcacheall __P((void));
struct inpcb;
extern struct secpolicy *ipsec4_getpolicybypcb
__P((struct mbuf *, u_int, struct inpcb *, int *));
extern struct secpolicy *ipsec4_getpolicybysock
__P((struct mbuf *, u_int, struct socket *, int *));
extern struct secpolicy *ipsec4_getpolicybyaddr
__P((struct mbuf *, u_int, int, int *));
struct inpcb;
extern int ipsec_init_pcbpolicy __P((struct socket *, struct inpcbpolicy **));
extern int ipsec_copy_pcbpolicy
__P((struct inpcbpolicy *, struct inpcbpolicy *));
extern u_int ipsec_get_reqlevel __P((struct ipsecrequest *, int));
extern int ipsec4_set_policy __P((struct inpcb *, int, caddr_t, size_t, int));
extern int ipsec4_get_policy __P((struct inpcb *, caddr_t, size_t,
struct mbuf **));
extern int ipsec4_delete_pcbpolicy __P((struct inpcb *));
extern int ipsec4_in_reject_so __P((struct mbuf *, struct socket *));
extern int ipsec4_in_reject __P((struct mbuf *, struct inpcb *));
struct secas;
struct tcpcb;
struct tcp6cb;
extern int ipsec_chkreplay __P((u_int32_t, struct secasvar *));
extern int ipsec_updatereplay __P((u_int32_t, struct secasvar *));
extern size_t ipsec4_hdrsiz __P((struct mbuf *, u_int, struct inpcb *));
extern size_t ipsec_hdrsiz_tcp __P((struct tcpcb *));
struct ip;
extern const char *ipsec4_logpacketstr __P((struct ip *, u_int32_t));
extern const char *ipsec_logsastr __P((struct secasvar *));
extern void ipsec_dumpmbuf __P((struct mbuf *));
extern int ipsec4_output __P((struct ipsec_output_state *, struct secpolicy *,
int));
extern int ipsec4_tunnel_validate __P((struct mbuf *, int, u_int,
struct secasvar *));
extern struct mbuf *ipsec_copypkt __P((struct mbuf *));
extern void ipsec_delaux __P((struct mbuf *));
extern int ipsec_addhist __P((struct mbuf *, int, u_int32_t));
extern int ipsec_getnhist __P((struct mbuf *));
extern void ipsec_clearhist __P((struct mbuf *));
#endif /* _KERNEL */
#ifndef _KERNEL
extern caddr_t ipsec_set_policy __P((char *, int));
extern int ipsec_get_policylen __P((caddr_t));
extern char *ipsec_dump_policy __P((caddr_t, char *));
extern const char *ipsec_strerror __P((void));
#endif /* !_KERNEL */
#endif /* _NETINET6_IPSEC_H_ */